Voltage supply arrangement and method for production of electrical power

ABSTRACT

A voltage supply arrangement is proposed, which provides a voltage from a first power range in a first operating mode and from a second power range in a second operating mode, to a first electrical load. The voltage supply arrangement includes a voltage converter which is coupled on the input side to a voltage input of the voltage supply arrangement and on the output side to a first connection of a first switch, which is connected at a second connection to a voltage output of the voltage supply arrangement for connection of a first electrical load. The voltage supply arrangement further includes a second switch, which is coupled at a first connection to the voltage input and at a second connection to the voltage output, and a drive circuit, which is configured to set the first and the second switch to the first or the second operating mode in response to a control signal.

RELATED APPLICATIONS

This Application is a Divisional Application of application Ser. No.11/413,423, which claimed priority of German Application DE102005020314.0. The priority of the Applications are hereby claimed andthe entirety thereof are hereby incorporated herein by reference.

BACKGROUND

A voltage supply arrangement is used, for example, in the field ofwireless communication devices in order to supply a power amplifier asan electrical load. The trend in modern mobile telephones to futuremultifunctional mobile communication appliances, with speech tomultimedia capability, for multiband and multistandard operationrequires the use of linear modulation types which are efficient over abroad bandwidth.

The linear modulation types result in linearity requirements for thepower amplifier. Further requirements for the power amplifier resultfrom the desire to achieve a long battery operating time. Since thepower amplifier represents a major component of the total powerconsumption of wireless communications devices, high energy utilizationefficiency is thus necessary.

The energy efficiency may be improved if the magnitude of the operatingvoltage of the power amplifier is matched to the required output power.This may be achieved by means of a switched-mode regulator or a voltageconverter which converts the battery voltage to a variable supplyvoltage, with which the power amplifier is operated.

SUMMARY OF THE INVENTION

The following presents a simplified summary in order to provide a basicunderstanding of one or more aspects of the invention. This summary isnot an extensive overview of the invention, and is neither intended toidentify key or critical elements of the invention, nor to delineate thescope thereof. Rather, the primary purpose of the summary is to presentone or more concepts of the invention in a simplified form as a preludeto the more detailed description that is presented later.

A voltage supply arrangement which can be operated in a first or in asecond operating mode and is configured to provide a voltage from afirst power range in the first operating mode and from a second powerrange in the second operating mode to a first electrical load comprisesa voltage converter whose input side is coupled to a voltage input ofthe voltage supply arrangement in order to supply an input voltage andat a voltage converter output to a first connection of a first switch.Furthermore, the voltage supply arrangement comprises the first switch,which is coupled at a second connection to a voltage output of thevoltage supply arrangement for connection of a first electrical load,and a second switch, which is coupled at a first connection to thevoltage input of the voltage supply arrangement and at a secondconnection to the voltage output of the voltage supply arrangement. Thevoltage supply arrangement also comprises a drive circuit, which has atleast one drive circuit input for supplying at least one control signal,is coupled at a first output to a control input of the first switch andat a second output to a control input of the second switch, and isconfigured to drive the first and the second switch in response to theat least one control signal. The voltage supply arrangement can supplyan electrical load with voltage in various power ranges, and can operateon an energy-efficient basis in the process.

A transmission arrangement comprises a voltage supply arrangement, amodulator, to one input of which a payload signal to be transmitted canbe supplied and which is configured to provide a modulated signal at oneoutput, a transmission amplifier, to one input of which the outputsignal from the modulator can be supplied and which comprises the poweramplifier and an output for emission of the signal to be transmitted,and an antenna, one input of which is connected to the output of thetransmission amplifier, and which is configured for transmission of thesignal.

In accordance with one method of the present invention, a voltage isproduced for an electrical load in a first or in a second power range.In this case, for example, an input voltage is provided at a voltageinput and is coupled to an input of a clocked DC/DC voltage converterand to a first connection of a second switch. A voltage at the input ofthe voltage converter is converted to a voltage at a voltage converteroutput by means of the voltage converter, which is coupled at thevoltage converter output to a first connection of a first switch. Thefirst and the second switch are driven in response to at least onecontrol signal such that the second switch is open and the first switchis closed in order to produce a voltage in the first power range, andthe first switch is open and the second switch is closed in order toproduce a voltage in the second power range. This is accomplished insuch a manner that the first electrical load is supplied with an outputvoltage at a voltage output which is coupled to a second connection ofthe first switch and to a second connection of the second switch and isused for connection of the first electrical load.

To the accomplishment of the foregoing and related ends, the inventioncomprises the features hereinafter fully described and particularlypointed out in the claims. The following description and the annexeddrawings set forth in detail certain illustrative aspects andimplementations of the invention. These are indicative, however, of buta few of the various ways in which the principles of the invention maybe employed. Other objects, advantages and novel features of theinvention will become apparent from the following detailed descriptionof the invention when considered in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is described with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference number in different instances in thedescription and the figures may indicate similar or identical items.

FIG. 1 illustrates a simplified schematic diagram of an example of avoltage supply arrangement for supplying a first electrical load.

FIG. 2 illustrates a simplified schematic diagram of an example of avoltage supply arrangement for supplying a first electrical load andfurther loads.

FIGS. 3A and 3B illustrate simplified schematic diagrams of an exampleof a voltage supply arrangement for supplying a transmission path of atransmission arrangement.

FIGS. 4A to 4D illustrate examples of embodiments of an electronicswitch.

FIG. 5 illustrates an example of an embodiment of a voltage converter.

DETAILED DESCRIPTION

One or more implementations of the present invention will now bedescribed with reference to the attached drawings, wherein likereference numerals are used to refer to like elements throughout, andwherein the illustrated structures are not necessarily drawn to scale.

According to one embodiment, the invention provides a voltage supplyarrangement having two operating modes. In the first operating mode, thevoltage supply arrangement can provide an output voltage from a firstpower range, and in the second operating mode it can provide an outputvoltage from a second power range, to a first electrical load.

The voltage supply arrangement comprises the voltage input for supplyingthe input voltage. This input voltage can be converted by the voltageconverter to a voltage which is available at the voltage converteroutput.

The voltage input of the voltage supply arrangement and the voltageconverter output of the voltage converter are each coupled to a switch.For example, the voltage converter output is coupled to the firstconnection of the first switch, and the voltage input of the voltagesupply arrangement is coupled to the first connection of the secondswitch.

The second connection of the first switch and the second connection ofthe second switch are coupled to the voltage output of the voltagesupply arrangement. The first electrical load can be connected to thisvoltage output. The drive circuit can be supplied with the at least onecontrol signal. The drive circuit is configured to select the first andthe second operating mode in response to the control signal, and todrive the first and the second switch appropriately.

The voltage converter is configured for the first power range. When thispower range is required for operation of the first electrical load, thenthe first operating mode can be selected by the drive circuit settingthe first switch to a closed state and the second switch to an openstate. When a power range outside the first power range is required,then the second operating mode can be selected by the drive circuit. Inthis operating mode, the second switch is set to be closed and the firstswitch is set to be open, so that the first electrical load is connecteddirectly to the input voltage.

One advantage of this embodiment of the voltage supply arrangement isthat the first electrical load is linked to the voltage input and isoperated with the aid of the input voltage when the first electricalload requires a power of a magnitude which this energy source cansupply. Thus, no voltage converter is connected in between, so that theelectrical power losses are extremely low.

When the electrical first load requires an electrical power in adifferent power range, then the voltage which is required by the firstelectrical load is provided by the voltage converter. The voltageconverter can be configured for this power range. This voltage supplyarrangement thus makes very efficient use of the input voltage, and asupply in two power ranges is made available to the first electricalload.

Since only two switches and one circuit for driving the two switches arerequired for operation in addition to the voltage converter, which isgenerally present in appliances such as these, this voltage supplyarrangement can be highly cost-efficient.

Alternatively, the first switch can be arranged on an input side of thevoltage converter, instead of an output side of the voltage converter.As an alternative to the first switch on the output side or the inputside of the voltage converter, the voltage converter can also beconfigured such that it can be switched off by a means foractivation/deactivation, such as by using a multiplexer, a switchselector, or a drive circuit.

In one embodiment, the voltage converter may take the form of a clockedDC/DC converter. The voltage converter may, for example, be configuredto provide a predetermined constant voltage at the voltage converteroutput.

The voltage supply arrangement may be configured such that the firstswitch is closed in the first operating mode and the second switch isclosed in the second operating mode, with the other switch in each casebeing open. The voltage supply arrangement is, for example, configuredsuch that the first switch and the second switch are not closed at thesame time.

The voltage converter may be configured to provide a voltage in thefirst power range, with the voltages in the first power range beinglower than the voltages in the second power range, in one example. Theelectrical power in the second power range can then be provided from theenergy source which is connected to the voltage input of the voltagesupply arrangement. The output voltage of the voltage converter is inthis embodiment less than the input voltage of the voltage supplyarrangement. The voltage converter may for this purpose comprise astep-down converter.

FIG. 1 shows one exemplary embodiment of a voltage supply arrangement 11for supplying a first electrical load 1. A voltage converter 2 isconnected at one input to a voltage input 3 of the voltage supplyarrangement 11. The voltage converter 2 converts the input voltage atthe voltage input 3 of the voltage supply arrangement 11 to a voltageconverter output voltage, which is produced at the voltage converteroutput 20.

A voltage output 6 of the voltage supply arrangement 11 is connected bymeans of a first switch 4 to the voltage converter output 20 of thevoltage converter 2, and by means of a second switch 5 to the voltageinput 3 of the voltage supply arrangement 11. The first electrical load1 is connected to the voltage output 6. A drive circuit 7 is used to setthe first and the second switch 4, 5.

The voltage converter 2, the drive circuit 7 and the first electricalload 1 are connected to a reference ground potential connection 8. Thedrive circuit 7 is connected via a first switch control line 14 to acontrol input of the first switch 4, and via a second switch controlline 15 to a control input of the second switch 5. The drive circuit 7is connected to the voltage input 3 for the power supply, and issupplied at its drive circuit input 34 with a control signal, by meansof a signal line 13, in order to preset the setting of the two switches4, 5.

Depending on the control signal, the drive circuit 7 switches the firstor the second switch 4, 5 to a closed state, and the respective otherswitch 4, 5 to an open state. When the first switch 4 is closed, thefirst electrical load 1 is supplied by the voltage converter 2. When thesecond switch 5 is closed, the first electrical load is supplied by theinput voltage.

The output voltage is thus produced in an energy-efficient manner in twodifferent power ranges for the first electrical load 1. The voltageconverter may be configured specifically for the requirements of thevoltage supply in only one power range, and thus occupies only a smallarea by comparison to a voltage converter that is operable to supply thefirst and the second power range.

The electrical load may comprise a power amplifier which is connected tothe voltage output. The drive circuit may, in one embodiment, beconfigured to supply the power amplifier in the second operating modefor high transmission powers and in the first operating mode fortransmission powers which are low in comparison with the secondoperating mode. For example, a typical voltage at the voltage output isabout 3.5 volts for the second power range, and is about 1 volt for thefirst power range.

In one example embodiment, a battery is coupled to the voltage input ofthe voltage supply arrangement. The battery may be a battery which canbe used only once. The battery may be a rechargeable battery.

The drive circuit, in one embodiment, is coupled at two outputs and bymeans of a first and a second switch control line to the first and thesecond switch, in order to drive the first and the second switch. Inanother embodiment, the drive circuit comprises at least one drivecircuit input for reception of the control signals in digital form, adigital part for processing of the control signals, an analog part forlevel conversion to analog signals, and two outputs for supply of analogsignals by means of the first and the second switch control line to thefirst and the second switch. In a further embodiment, it has at leastone drive circuit input for reception of the control signals in analogform. In another embodiment, the drive circuit comprises two outputs foremission of digital signals by means of the first and the second switchcontrol line to the first and the second switch, which in thisembodiment are configured for processing digital signals.

In an application in a wireless communication device, the second switchmay be set to a closed state and the first switch to an open state, inorder to couple the power amplifier to the voltage input of the voltagesupply arrangement for transmission based on the Global System forMobile Communication method, the GSM method for short. Further, thefirst switch can be set to a closed state and the second switch to anopen state in order to couple the power amplifier to the voltageconverter output for transmission using the Wideband Code DivisionMultiple Access method, the W-CDMA method for short. The power amplifiercan thus be supplied with a voltage which can be provided from thebattery for the GSM method, and with a lower voltage than the voltagewhich can be provided from the battery for the W-CDMA method. Oneadvantage of the voltage supply arrangement is that the gain linearityis improved by supplying the power amplifier with different voltages.

The voltage supply arrangement may have an additional or second voltageoutput, which is connected directly to the voltage converter output foroperation of a second electrical load.

The voltage supply arrangement may have at least one additional voltageoutput, which is coupled to at least one additional or second voltageconverter output and is used for connection of at least one third of theelectrical load, which is supplied with a voltage whose magnitudediffers from the magnitude of the voltage at the voltage converteroutput.

In another embodiment, the voltage supply arrangement may have at leastone additional output, which is coupled to an additional output of thevoltage converter and provides voltages which differ from the voltage atthe voltage converter output or voltage converter additional output onthe basis of characteristics such as noise, harmonic content, internalresistance, driver capability, fluctuation width or temperaturestability.

A third operating mode can be provided, with a third power range, inwhich no energy is made available at the voltage output of the voltagesupply arrangement to the first electrical load. The first electricalload can thus be switched off. The drive circuit may be configured toselect the third operating mode by setting both switches to the openposition.

In another embodiment, the drive circuit may be configured to identifyan overload of the first electrical load, for example, using an overloaddetector, and to open the first or the second switch in the event ofthis overload. A characteristic of overloading of the first electricalload may be an excessively high temperature of the first electricalload. The overload may be caused by an excessively high current flowthrough the first electrical load, or by an excessively high voltageacross the first electrical load. Further characteristic features ofoverloading may thus be an excessively high current flow or anexcessively high voltage. The voltage supply arrangement may thus beconfigured to determine the temperature of the first electrical load,the current flowing through the voltage output and/or the voltage at thevoltage output, and to supply the value determined in this way inresponse to the temperature of the current and/or of the voltage to thedrive circuit in order to change the switch settings.

If the second switch, which is configured to supply the first electricalload with an electrical power in the higher power range, is closedbefore the occurrence of the overload, then the drive circuit can beconfigured to switch this switch to the open state, and the first switchto the closed state, on identification or detection of the overload.

If the first switch, which is configured to supply the first electricalload with the lower power range, is closed before the occurrence of theoverload, then the drive circuit is configured to set both switches tothe closed state on identification or detection of the overload.

The input voltage of the voltage supply arrangement may be configured tobe higher than the typical input voltages which occur during operation,during a process in which the battery is being charged or when thevoltage supply arrangement is being used in a mobile radio and thespatial arrangement of the antenna of the mobile radio with respect to ametallic body is disadvantageous. The drive circuit is thus configuredsuch that the output voltage is detected and the second and/or the firstswitch are/is driven such that the output voltages for supplying thefirst electrical load occur exclusively in a permissible range and thusnot above a predetermined voltage level of the voltage output. During anovervoltage, the second and/or the first switch may be switched to theopen state.

The second switch may comprise a variable resistance, so that the outputvoltage falls as a result of the voltage drop across the resistance. Theresistance can thus be set such that the first electrical load is stillsupplied with the required power, but is protected against anovervoltage. In accordance with Ohm's Law, the voltage drop is theproduct of the resistance value of the resistance and the currentthrough the first electrical load. Accordingly, it may be advantageousfor the second switch to comprise a resistance, since the firstelectrical load is still in operation and can be configured in such amanner that it is configured with little complexity to cope only with avoltage up to a predetermined permissible output voltage limit. Thismakes it possible to reduce the implementation costs.

In order to set the resistance of the second switch, the drive circuitcan determine the output voltage of the voltage supply arrangement bymeans of a second voltage tap line. In another embodiment, the drivecircuit can additionally determine the input voltage of the voltagesupply arrangement by means of a first voltage tap line, and candetermine a signal for controlling the switch, from the output voltageand the input voltage. In a further embodiment, the resistance of thefirst switch can be set in an analogous manner.

The voltage converter requires only a small amount of power when thecurrent at the voltage converter output and at the voltage converteradditional output is equal to zero. These power losses can be reducedfurther by the voltage supply arrangement, in a further embodiment,having a third switch and a third switch control line. When the firstelectrical load is being operated in the second power range, the thirdswitch can be switched to an open state. When a second power range hasbeen activated in order to supply the first electrical load, thistherefore avoids the voltage converter making available a voltage in thefirst power range.

The voltage level which is provided from the voltage converter may beadjustable in order that the output voltage can be matched even moreaccurately to the requirements in the first power range. The voltageconverter may also be configured such that it can be switched off inorder to reduce power losses. Both can be achieved by linking thevoltage converter to the drive circuit by means of a voltage convertercontrol line.

FIG. 2 illustrates one exemplary embodiment of a voltage supplyarrangement 11 for supplying a first, a second, and a third electricalload 1, 9, 10, respectively.

A voltage supply arrangement 11 is used to provide a voltage from afirst power range in a first operating mode, and from a second powerrange in a second operating mode, to a first electrical load 1. Thevoltage supply arrangement 11 comprises a voltage converter 2, whoseinput side is coupled to a voltage input 3 of the voltage supplyarrangement 11, and whose output side is coupled to a first connectionof a first switch 4, which is connected to a second connection with avoltage output 6 of the voltage supply arrangement 11 for connection ofa first electrical load 1. The voltage supply arrangement 11 alsocomprises a second switch 5, which is coupled at a first connection tothe voltage input 3 and at a second connection to the voltage output 6,and a drive circuit 7, which is configured to set the first and thesecond switch 4, 5 to the first or the second operating mode, inresponse to a control signal.

The voltage output 6 of the voltage supply arrangement 11 is coupled bymeans of the second electrical switch 5 to the voltage input 3 of thevoltage supply arrangement 11. The voltage output 6 is linked by meansof the first switch 4 to the voltage converter output 20 of a voltageconverter 2. The voltage converter 2 converts an input voltage which isapplied to the input of the voltage supply arrangement 11 to a voltageconverter output signal, which is produced at the voltage converteroutput 20.

The second electrical load 9 is connected by means of a further orsecond voltage output 21 of the voltage supply arrangement 11 to thevoltage converter output 20 of the voltage converter 2.

The third electrical load 10 is coupled by means of an additional orthird voltage output 23 of the voltage supply arrangement 11 to anadditional voltage converter output 22 of the voltage converter 2.According to this exemplary embodiment, the voltage converter 2 thussupplies the second electrical load 9 and the third electrical load 10with two different voltages.

The drive circuit 7 is linked via a first switch control line 14 to thefirst switch 4, and via a second switch control line 15 to the secondswitch 5.

A plurality of signal lines 13 are in this exemplary embodimentconnected to a drive circuit input 34 of the drive circuit 7. The signallines 13 are used to supply a signal to the drive circuit 7, so that thedrive circuit 7 selects the operating mode of the voltage supplyarrangement 11, and controls the first switch 4 and the second switch 5,in response to the signal.

The drive circuit 7 is configured to detect the input voltage by meansof a first voltage tap line 16. This can be done by sampling the line ata point between the voltage input 3 and the first connection of thesecond switch 5. The drive circuit 7 is configured to detect the outputvoltage by means of a second voltage tap line 17 for this purpose. Forthis purpose, it has a second voltage tap line 17, which detects theoutput voltage at a point on the line between the second connection ofthe second switch 5 and the voltage output 6 of the voltage supplyarrangement 11. The voltage may also be tapped off at the connections ofthe lines. If the output voltage is higher than a voltage range that ispermissible for operation of the first electrical load 1, the resistanceof the second switch 5, comprising a controllable resistance, isadjusted such that this results in the permissible voltage range notbeing overshot.

A third switch 18 is provided between the voltage input 3 of the voltagesupply arrangement 11 and the input of the voltage converter 2. Thethird switch 18 can thus be opened and closed, as an alternative toclosing and opening of the first switch 4, if the second electrical load9 and the third electrical load 10 require electrical power exclusivelywhen the operation of the first electrical load 1 requires a power inthe second power range. A third switch control line 27 is provided inorder to control the third switch 18.

The electrical power which is provided from the voltage converter may beadjustable. It may also be possible to select a power level of 0, thatis to say with the voltage converter switched off. A voltage convertercontrol line 35 for this purpose connects the voltage converter 2 andthe drive circuit 7.

The first electrical load 1 is thus electrically supplied with power inthe desired power range at the input voltage by closing the switch 5 orat the output voltage of the voltage converter 2 by closing the firstswitch 4. The first electrical load 1 is thus supplied in a veryenergy-efficient manner. A further advantage of the voltage supplyarrangement 11 is that the first electrical load 1 is protected againstovervoltages.

In one embodiment of a transmission arrangement, the modulator can beconnected to a further voltage output and to at least one additionalvoltage output of the voltage supply arrangement.

A complex signal which is to be processed in the transmissionarrangement may in one embodiment be represented in polar coordinates,that is to say in amplitude and phase. The amplitude and phase can beprocessed individually. The amplitude signal and the phase signal aregenerally joined together during the production of the signal to betransmitted from the antenna. The amplitude and the phase may becombined in a polar modulator. The amplitude and the phase are combinedin a polar transmitter, and the modulator and the transmission amplifieras well as the power amplifier in the transmission amplifier areconfigured to process the signals on the basis of a polar transmitterprinciple.

The first and/or the second switch may be configured to modulate theamplitude of the signal to be transmitted by having a further controlinput for supplying the payload signal or a component of the payloadsignal, particularly when in the form of a controllable resistance. Inone embodiment, the first switch may for this purpose be connected atits further control input by means of a fourth switch control line tothe modulator, and/or the second switch may be connected at its furthercontrol input by means of a fifth switch control line to the modulator.

In one embodiment, the power amplifier comprises a bipolar transistor asan amplifying component and a controllable resistor, which is coupled tothe base of the bipolar transistor and is configured to set the basecurrent. A resistance control line connects the controllable resistanceto the drive circuit. The setting of the base current results in thesetting of the operating point of the bipolar transistor, and thus ofthe power provided from the power amplifier. This embodiment can be usedin a transmission arrangement which is configured for the W-CDMA method,since, in the W-CDMA method, the transmission process is carried out intime windows, or slots, and a mean power amplifier power level isdefined for each slot. One advantage of this embodiment is that thepower in the first power range, and hence the power consumption of thetransmission arrangement, are further reduced when carrying out theW-CDMA method.

FIG. 3A shows one embodiment of the proposed voltage supply arrangement11 for supplying a transmission arrangement. The transmissionarrangement has the voltage supply arrangement 11 for supplying thetransmission amplifier 25. The transmission amplifier 25 comprises apower amplifier 19. A modulator 24 is connected at its output to oneinput of the transmission amplifier 25, which is in turn coupled to anantenna 26.

The modulator 24 is connected to a further voltage output 21, and to anadditional voltage output 23 of the voltage supply arrangement 11. Thevoltage output 21 is connected to a voltage converter output 20, and thevoltage additional output 23 is connected to a voltage converteradditional output 22 of a voltage converter 2.

At its input, the voltage converter 2 is linked to the voltage input 3of the voltage supply arrangement 11, and is used to convert an inputvoltage to the voltage supply arrangement 11. The voltage converteroutput 20 is coupled via a first switch 4 to a voltage output 6 of thevoltage supply arrangement 11. The voltage input 3 of the voltage supplyarrangement 11 is in turn coupled via a second switch 5 to the voltageoutput 6 of the voltage supply arrangement 11. The transmissionamplifier is connected to the voltage output 6 in such a manner that thepower amplifier 19 is supplied at a supply input with the output voltagefrom the voltage supply arrangement 11.

A drive circuit 7 is connected by means of a first switch control line14 to the first switch 4, and by means of a second switch control line15 to the second switch 5. At its control input or control inputs 34,the drive circuit 7 receives, by means of the signal lines 13, a controlsignal which allows the drive circuit 7 to select the desired powerrange by closing the switch 4 or the switch 5.

The first switch 4 is closed in order to supply a voltage in the firstpower range to the transmission amplifier 25. The second switch 5 isclosed in order to supply a voltage in the second power range to thetransmission amplifier 25. The other switch is in each case open.

A battery 12 is connected to the voltage input 3 of the voltage supplyarrangement 11.

The modulator 24 converts a payload signal U_(IN)—MOD to be transmittedand which is applied to an input to a modulated output signal. Thisoutput signal from the modulator 24 is converted by the transmissionamplifier 25 to a signal U_(OUT)—PA to be transmitted by the antenna 26.

The voltage converter 2 converts the input voltage, which is applied tothe voltage input 3, to a voltage which is produced at the voltageconverter output 20, and to a further voltage which is produced at anadditional voltage converter output 22.

The voltage converter 2 thus supplies two different supply voltages forsupplying the modulator 24.

In this exemplary embodiment, the first power range is lower than thesecond power range. In this case, when the power demand for thetransmission amplifier 25 is low, the transmission amplifier 25 issupplied with the output voltage from the voltage converter 2 by closingthe first switch 4.

In the second power range, that is to say the higher-power range, thetransmission amplifier 25 is coupled directly to the battery voltage byclosing the switch 5. The transmission amplifier 25 is thus providedwith the maximum possible power which is required between the mobileradio and the transmission station for some modulation types and forcertain spatial circumstances.

The voltage converter 2 is in this example thus configured exclusivelyto supply voltage in a power range with low voltage values. In a powerrange with high voltage values, the transmission amplifier 25 obtainsthe electrical voltage directly from the input voltage, which is linkedto the battery 12.

The first switch 4 is connected to the modulator 24 at a further controlinput by means of a fourth switch control line 36 and, by analogy, thesecond switch 5 is connected to the modulator 24 at its further controlinput by means of a fifth switch control line 37.

The energy which is stored in the battery 12 is thus used highlyefficiently in this arrangement.

FIG. 3B illustrates an exemplary embodiment of a development of thevoltage supply arrangement for supplying a transmission path in atransmission arrangement as shown in FIG. 3A. To the extent that the twocircuits correspond in terms of components, circuitry and function,their description will not be repeated at this point. In addition, FIG.3B has a bipolar transistor 47, a resistance control line 46, acontrollable resistor 45 and a fixed resistor 53. The bipolar transistor47 is an amplifying component of the power amplifier 19, and representsthe central amplifier element of the power amplifier 19.

The controllable resistor 45 is coupled to the base of the bipolartransistor 47. The base is connected to the reference ground potentialconnection 8 by means of the fixed resistor 53. The emitter of thebipolar transistor 47 is coupled to the reference ground potentialconnection 8. A resistive divider, comprising the controllable resistor45 and the fixed resistor 53, is used to set a base current, and hencean operating point of the bipolar transistor 47. The resistance controlline 46 which controls the controllable resistor 45 is connected to afurther output of the drive circuit 7.

Adjustment of the controllable resistor 45 results in adjustment of theoperating current of the bipolar transistor 47 in the power amplifier19, and thus the power which is provided from the power amplifier 19.This further reduces the power consumption of the transmissionarrangement.

The first and/or the second switch may comprise controllable switches,which have only the open or closed states.

The first and/or the second switch comprise a controllable resistance,so that the first or the second switch has not only the two states openand closed.

The first and/or the second switch may each have an electronic switch,which comprises at least one control input, a first connection and asecond connection. Alternatively, the first and/or the second switch maybe in the form of micromechanical relays.

The first and/or the second switch may be in the form of linearregulators or a linear regulator, which linearly regulate or regulatesan output voltage between two load connections in response to a voltageat a control input.

The electronic switch with or without the function of a controllableresistance and with or without the function of a linear regulator maycomprise at least one diode or at least one bipolar transistor, or atleast one field-effect transistor. The diode may be apositive-intrinsic-negative diode. One advantage of this solution isthat this makes it possible to provide the first and/or second switch ina semiconductor body.

The field-effect transistor, for example, may be provided in order toproduce the electronic switch has a sink connection, or drain, a sourceconnection, and a control connection, or gate. When the voltage betweenthe drain connection and the source connection is small, there is alinear relationship between this voltage and the current which flowsthrough the drain connection. In this range, the path in thefield-effect transistor between the drain connection and the sourceconnection can be described to a good approximation as a resistancewhich can be varied between high values and low values electronically byvariation of a voltage between the gate connection and the sourceconnection. The high resistance values correspond to the state when theswitch is open, and the low resistance values correspond to the statewhen the switch is closed. In the intermediate range, the switch acts asa controllable resistance. This may be used to produce a constant outputvoltage at the second connection of the electronic switch. In thisembodiment, the electronic switch may thus comprise a linear regulator.

The field-effect transistor may be a metal oxide semiconductorfield-effect transistor, or MOSFET for short. One alternative may be ajunction field-effect transistor. The junction field-effect transistorcan have an n-channel, that is to say the current charge carriers areelectrons.

The first and the second switch may comprise at least one furthertransistor or a current source or a voltage source as well as at leastone passive component such as a capacitor, a resistor, an inductance ora diode, in order to supply the switching elements with drive signalsand in order to reduce voltage spikes during the switching processes.

The electronic switch may comprise at least one n-channel field-effecttransistor and one p-channel field-effect transistor. In one embodimentof the electronic switch, an n-channel field-effect transistor and ap-channel field-effect transistor are connected in series. In oneexample, the series-connected field-effect transistors may be anormally-on n-channel MOSFET and a normally-on p-channel MOSFET.

The electronic switch may comprise a transmission unit with a controlinput, or transmission gate.

One embodiment of the electronic switch may have two field-effecttransistors connected in parallel in a differential circuit. Oneembodiment of the electronic switch may be an n-channel MOSFET and ap-channel MOSFET connected in parallel, with both MOSFETs advantageouslybeing normally-on MOSFETs.

The electronic switch may be in the form of a linear regulator whichcomprises a comparator and a p-channel MOSFET. The p-channel MOSFET maybe used as a switch with the open and closed states, and as anelectronically controllable resistance. In this embodiment, a firstcomparator input may be connected to the control input of the electronicswitch. One output of the comparator may be connected to the controlconnection of the p-channel MOSFET. A load connection of the MOSFET mayform the first connection of the electronic switch, and a further loadconnection of the MOSFET may form the second connection of theelectronic switch. The second connection of the electronic switch may inthis case be connected to the reference ground potential connection viaa resistive divider, comprising a first and a second resistance. Asecond comparator input may be connected to a node of the resistivedivider, which is located between the first resistor and the secondresistor. In this embodiment of the electronic switch, it is set avoltage at the second connection of the electronic switch in response toa voltage which is applied to the control input of the electronicswitch.

In this embodiment of the electronic switch, the output voltage of thevoltage supply arrangement can be restricted to a permissible voltage ifthe input voltage of the voltage supply arrangement has an excessivelyhigh value.

For this purpose, the voltage at the control input of the electronicswitch can be set to a maximum permissible voltage value if the outputvoltage of the voltage supply arrangement exceeds this maximum value.

This embodiment of the electronic switch which operates as a linearregulator may be used to increase the power of the power amplifier. Apredetermined increase in the voltage at the control input of theelectronic switch can be used to increase the output voltage of thevoltage supply arrangement, which represents an operating voltage forthe power amplifier, from a value of 0 to a value which is virtually thesame as the input voltage of the voltage supply arrangement. The outputpower of the power amplifier may in this case be approximatelyproportional to the square of the output voltage of the voltage supplyarrangement.

In one embodiment of a transmission method, the transmission process maybe carried out in time slots. A first subscriber can transmit in onetime slot and further subscribers can transmit in further time slotsbefore the first subscriber can transmit again. During one time slot,the power amplifier can thus be supplied with a power such that thepower is increased to a predetermined value starting from a rest stateat the start of a time slot, and is reduced at the end of the time slot.This rise and fall of the power may be described as a pulse, or burst.This may be required, for example, in the GSM method. Thus, for thistransmission method, the electronic switch comprises a linear regulatorfor selection of the power to be provided to the power amplifier.

This embodiment of the electronic switch can be used with the functionof a linear regulator in order to modulate the output voltage of thevoltage supply arrangement, which at the same time is the operatingvoltage for the power amplifier, such that the amplitude modulation isadditionally applied to a phase-modulated input signal which has beenamplified in a relevant power stage. The voltage which is applied to thecontrol input of the electronic switch can be modulated for thispurpose. In one embodiment, the modulation can be applied to the outputstage, with the further stages being directly connected to the input ofthe voltage arrangement, and thus to the battery. In one embodiment, twoor more stages of a polar amplifier in the polar modulator or in thepolar transmitter can be connected to one or more suitable regulators,with the modulation being applied in this way.

The electronic switch with the function of a linear regulator may have ap-channel MOSFET in the form of a depletion type MOSFET. A powertransistor in the power amplifier may be a field-effect transistor whichis connected by its source connection to the reference ground potentialconnection. A power transistor may, however, also be a bipolartransistor, which is connected by its emitter connection to thereference ground potential. These two embodiments are advantageous incomparison to so-called floating operation, in which sources andemitters are not connected to the reference-ground potential, forthermal and radio-frequency reasons.

The first and the second switch may be physically identical. The secondswitch may be configured to be different to the first switch in order tomake it possible for one of the two switches to carry out an additionalfunction, such as protection against short-circuiting.

FIG. 4A illustrates one example of an embodiment of an electronic switch29. This may be used as the first, the second and/or the third switch 4,5, 18 in FIGS. 1, 2, 3 A to 3 B.

The first, second and/or third switch 4, 5, 18 in FIGS. 1, 2, 3 A to 3 Bmay be an electronic switch 29 with open and closed states. However, itmay also be a variable resistance.

Both alternatives can be provided by a bipolar transistor or a circuitcomprising bipolar transistors. It may be advantageous for one switch tobe in the form of a p-channel metal oxide semiconductor field-effecttransistor MOSFET, because the switch can be controlled with less power.A switch in the form of an n-channel MOSFET may be advantageous becausethe internal resistance is less owing to the greater mobility ofelectrons in comparison to holes in semiconductor materials such assilicon, germanium and gallium arsenide.

A MOSFET may be in the form of a depletion-type MOSFET. A MOSFET in theform of an enhancement type MOSFET is advantageous because the MOSFET isno longer switched on when the voltage between its gate connection andits source connection is 0 volts. A circuit arrangement comprisingMOSFETs can also be provided, instead of a single MOSFET.

As an example of the first, second and/or third switch 4, 5, 18, butwithout any restriction to generality, FIG. 4A shows the electronicswitch 29, comprising an n-channel enhancement type MOSFET 30. A controlconnection 31 of the electronic switch 29 is connected to asemiconductor switch control line 28, and the electronic switch 29 has afirst and a second connection 32, 33, between which there is acontrolled path. The semiconductor switch control line 28 may be thefirst, the second, the third, the fourth or the fifth switch controlline 14, 15, 27, 36, 37 in FIGS. 1, 2, 3 A and 3 B.

FIG. 4B shows a further exemplary embodiment of an electronic switch 69,which may be used as the first, the second and/or the third switch 4, 5,18, respectively, in FIGS. 1, 2, 3 A and 3 B. The electronic switch 69in FIG. 4B comprises a field-effect transistor 48. The field-effecttransistor 48 has a source connection, a drain connection and a gateconnection. The gate connection of the field-effect transistor 48 isconnected to a gate connection 61 of the electronic switch 69, to whichthe semiconductor switch control line 68 is connected.

The field-effect transistor 48 shown in FIG. 4B may be a junctionfield-effect transistor. The junction field-effect transistor may be inthe form of an n-channel junction field-effect transistor. In thisembodiment, the field-effect transistor 48 is connected by its sourceconnection to the second connection 63 of the electronic switch 69, andby its drain connection to the first connection 62 of the electronicswitch 69.

When the voltage between the gate connection and the source connectionof the field-effect transistor 48 is equal to the voltage between thedrain connection and the source connection of the field-effecttransistor 48, and is thus equal to the voltage at the first connection62 of the electronic switch 69, then the electronic switch 69 is in aclosed state. When the voltage between the gate connection and thesource connection is less than a threshold voltage U_(P), also referredto as a pinch-off voltage, then the electronic switch 69 is in an openstate. When the voltage between the gate connection and the sourceconnection is between the threshold voltage Up and the voltage betweenthe drain connection and the source connection, then the field-effecttransistor 48 acts as a controllable resistor.

FIG. 4C illustrates a characteristic of the n-channel junctionfield-effect transistor based on one embodiment. This shows an outputcharacteristic for which a drain current I D, which flows through thedrain connection of the n-channel junction field-effect transistor, isillustrated in response to a voltage U_(DS) which is present between thedrain connection and the source connection of the field-effecttransistor. The family parameter for the various curves is a voltageU_(GS) between the gate connection and the source connection of thefield-effect transistor. A curve U_(K) is also shown, which illustratesthe transition from a parabolic relationship between the drain currentI_(D) and the voltage U_(DS) between the drain connection and the sourceconnection, to the saturation region.

FIG. 4D illustrates one embodiment of an electronic switch 79 with alinear-regulator function. The electronic switch 79 comprises ap-channel MOSFET 49 and a comparator 50. The electronic switch 79 may beone embodiment of the second switch 5 in FIG. 1, 2, 3 A or 3 B.

The p-channel MOSFET 49 has a drain connection, a source connection, asubstrate connection and a gate connection. The source and substrateconnections of the p-channel MOSFET 49 are connected to the voltageinput 3 of the voltage supply. A battery may be connected to thisvoltage input 3. The drain connection of the p-channel MOSFET 49 isconnected to a second connection 73 of the electronic switch 79. Thesecond connection 73 is connected to the voltage output 6 (which is notshown) of the voltage supply arrangement. A power amplifier can beconnected to this voltage output 6. The voltage at the voltage output 6is used in this embodiment as the operating voltage for the poweramplifier.

The control connection of the field-effect transistor 49 is connected toone output of the comparator 50. In this embodiment, a voltage which ispresent at the gate connection 71 of the electronic switch 79 isconnected to a negative input of the comparator 50. The drain connectionof the field-effect transistor 49 is connected via a resistive divider,comprising a first resistor 51 and a second resistor 52, to thereference ground potential connection 8. A voltage at a node between thefirst resistor 51 and the second resistor 52 is connected to a positiveinput of the comparator 50. In order to operate the comparator 50, it isconnected to the voltage input 3 of the voltage supply, and to thereference ground potential connection 8.

When the voltage U_(A) at the second connection 73 of the electronicswitch 79 falls, then the output of the comparator 50 becomes negative.In consequence, in this embodiment, the current through the field-effecttransistor 49 can rise, so that the voltage U_(A) at the secondconnection 73 rises, and reaches the predetermined value.

The output voltage of the second connection 73 of the electronic switch79, which may be the second switch 5 in FIGS. 1, 2, 3A and 3 B, can thusbe adjusted in response to the control voltage U_(ST).

FIG. 5 illustrates an example of an embodiment of a voltage converter 2which can be used in the embodiment shown in FIGS. 1, 2, 3A to 3 B.

The voltage converter 2 in FIG. 5 comprises a step-down converter, whichconverts an input voltage U_(E) to an output voltage U_(A).

The input of the voltage converter 2 is coupled to the voltage input 3of the voltage supply arrangement 11. The input of the voltage converter2 is connected to a first connection of a voltage converter switch 40. Asecond connection of the voltage converter switch 40 is connected to afirst connection of a voltage converter diode 42, and to a firstconnection of a voltage converter inductance 43. A second connection ofthe voltage converter diode 42 is linked to the reference groundpotential connection 8.

The voltage converter diode 42 is connected such that, when the voltageU_(E) at the input of the voltage converter 2 is positive, the secondconnection leads to a p-doped region, and the first connection leads toan n-doped region in the voltage converter diode 42.

A second connection of the voltage converter inductance 43 is connectedto a first connection of a voltage converter capacitor 44, and iscoupled to the voltage converter output 20 of the voltage converter 2.The second connection of the voltage converter capacitor 44 is connectedto the reference ground potential connection 8.

The voltage converter switch 40 is clocked by a voltage convertercontroller 41 in order to set the output voltage U_(A).

When the voltage converter switch 40 is in a closed state, the currentthrough the voltage converter inductance 43 rises, and the voltageconverter capacitor 44 is charged. The voltage U_(D) across the voltageconverter diode 42 is equal to the input voltage U_(E). The voltageconverter diode 42 is reverse-biased.

When the voltage converter switch 40 is in an open state, the currentthrough the voltage converter inductance 43 decreases from its maximumvalue, which it reaches at the switching time. The current continues tocharge the voltage converter capacitor 44, however. The voltage U_(D)across the voltage converter diode 42 decreases. When the voltage U_(D)becomes negative, then a current flows through the voltage converterdiode 42.

The output voltage U_(A) is primarily a function of an on and offswitching time of the voltage converter switch 40, of a current flowingthrough the voltage converter output 20, of the input voltage U_(E) andof an inductance value of the voltage converter inductance 43. Anyripple on the output voltage U_(A) is primarily a function of thecapacitance of the voltage converter capacitor 44.

The two switches and the drive circuit may be formed in three dedicatedsemiconductor bodies. The two switches and the drive circuit can beproduced together in one semiconductor body, because this reduces thenumber of contacts.

The voltage converter can likewise be produced in a dedicatedsemiconductor body. In an alternative embodiment, a voltage converterwhich already exists in an overall system such as a mobile radio can beused to provide a voltage.

In a further embodiment, the voltage converter, the two switches and thedrive circuit are integrated in a common semiconductor body.

The components may also be provided in one semiconductor body, whichcomprises a central power/battery management circuit and supplies theadditional modules in a mobile radio.

In an alternative embodiment, the two switches and the drive circuit areintegrated in a hybrid or monolithic form in a semiconductor body in themodule in order to provide a decentralized power supply for a module.

In a further embodiment, the power amplifier is integrated together withat least the two switches and the voltage converter in one semiconductorbody.

Complementary metal oxide semiconductor CMOS, bipolar complementarymetal oxide semiconductor BICMOS, double diffused metal oxidesemiconductor DMOS or laterally diffused metal oxide semiconductor LDMOSmay be used as integration techniques for the switches, for the drivecircuit or for the voltage converter, and for the entire voltage supplyarrangement.

For other developments of the voltage supply arrangement, reference ismade to the dependent claims.

In one embodiment of the method, the input voltage is initiallyproduced. This input voltage is applied to the voltage converter, whichconverts it to a different voltage, which is produced by it at itsvoltage converter output.

One of the two voltages that are produced may then be made available atthe voltage output of the voltage supply arrangement, depending on theswitch position of the two switches. The first electrical load to besupplied can be connected to the voltage output.

The setting as to which output voltage and/or the power range in whichan output voltage is made available at the voltage output may beachieved by means of two switches and one drive circuit. If only thefirst switch is closed, then the voltage which is made available by thevoltage converter may be then applied to the voltage output of thevoltage supply arrangement. If only the second switch is closed, thenthe input voltage to the voltage supply arrangement may be applied tothe voltage output of the voltage supply arrangement.

One advantage of this method is that the first electrical load can belinked to a supply with different power ranges. Generally, only lowpower losses occur in the second power range, since the switches, lines,connections and drive circuit are designed to have low losses.

In the first power range, losses occur primarily during the voltageconversion. Since the voltage converter provides a voltage within arestricted power range, it can be configured specifically for this powerrange, and thus to be particularly energy-efficient.

In one embodiment, a power amplifier can be supplied with an outputvoltage that is produced at the voltage output.

In one exemplary embodiment, in the case of an application in a wirelesscommunication appliance, the two switches can be driven such that thefirst switch is closed and the second switch is open, in order to couplethe power amplifier to the voltage input of the voltage supplyarrangement for transmission using the GSM method, and the first switchis closed and the second switch is open in order to couple the poweramplifier to the voltage converter output for transmission using theW-CDMA method.

In another embodiment, the output power of the power amplifier is variedfrom a low value to a high value using a method whose timing ispredetermined exactly, such that the first and/or the second switch,comprising a controlled resistance or resistances, are/is driven suchthat the power that is supplied to the power amplifier risesappropriately. This embodiment is advantageous in a transmissionarrangement configured for the GSM method.

In one embodiment, a battery voltage can be provided at the voltageinput by means of a battery.

In another embodiment, the first switch can be closed, and the secondswitch can be opened, in order to provide electrical power to the firstelectrical load in a low power range, and the second switch can beclosed, and the first switch opened, in order to provide electricalpower in a high power range.

The identification of an overload in the first electrical load can leadto opening of the switch by means of which the first electrical load issupplied with voltage at this time.

In order to identify an overvoltage, the input voltage and/or the outputvoltage of the voltage supply arrangement can be sampled, and theresistance of the second and/or first switch, comprising a controllableresistance, can be adjusted in such a manner that the output voltage ismaintained within a predetermined permissible range, so that noovervoltage occurs at the voltage output.

In one embodiment, one or more control signals is or are supplied to theinput side of the drive circuit, and the first and the second switch aredriven by the drive circuit in such a way that the first electrical loadis supplied with electrical power corresponding to the control signal orthe control signals.

Non-overlap times are advantageously set in order to prevent one of thetwo switches from being closed before the other switch has been opened.

With regard to other developments of the method, reference is made tothe dependent claims.

In summary, the proposed principle can provide:

-   -   better efficiency of energy utilization compared with a voltage        supply arrangement with a voltage converter and without        switches,    -   a cost-effective solution for a voltage supply,    -   a design of the voltage converter for exclusively one power        range, which allows an implementation that saves chip area and        thus cost,    -   a volume-saving implementation overall,    -   the capability to protect the first electrical load against        overloading,    -   the capability to supply further electrical loads from the        voltage converter and thus to provide a highly flexible voltage        supply arrangement.

Although the invention has been shown and described with respect to oneor more implementations, equivalent alterations and modifications willoccur to others skilled in the art based upon a reading andunderstanding of this specification and the annexed drawings. Theinvention includes all such modifications and alterations and is limitedonly by the scope of the following claims. In addition, while aparticular feature or aspect of the invention may have been disclosedwith respect to only one of several implementations, such feature oraspect may be combined with one or more other features or aspects of theother implementations as may be desired and advantageous for any givenor particular application. Furthermore, to the extent that the terms“includes”, “having”, “has”, “with”, or variants thereof are used ineither the detailed description or the claims, such terms are intendedto be inclusive in a manner similar to the term “comprising.” Also, theterm “exemplary” is merely meant to mean an example, rather than thebest. It is also to be appreciated that layers and/or elements depictedherein are illustrated with particular dimensions relative to oneanother (e.g., layer to layer dimensions and/or orientations) forpurposes of simplicity and ease of understanding, and that actualdimensions of the elements may differ substantially from thatillustrated herein.

1. A transmission arrangement comprising: a voltage supply arrangementwhich can be operated in a first or in a second operating mode and isconfigured to provide a voltage in the first operating mode from a firstpower range, and from a second power range in the second operating mode,to a first electrical load, comprising: a voltage converter whose inputside is coupled to a voltage input of the voltage supply arrangement inorder to supply an input voltage and at a voltage converter output to afirst connection of a first switch; the first switch, which is coupledat a second connection to a voltage output of the voltage supplyarrangement for connection of the first electrical load; a secondswitch, which is coupled at a first connection to the voltage input ofthe voltage supply arrangement and at a second connection to the voltageoutput of the voltage supply arrangement; and a drive circuit, which hasat least one drive circuit input for supplying at least one controlsignal, coupled at a first output to a control input of the first switchand at a second output to a control input of the second switch, and isconfigured to drive the first and the second switch in response to theat least one control signal; a modulator which has an input forsupplying a payload signal to be transmitted, and has an output forproviding a modulated signal; a transmission amplifier, which isconnected at one input to the output of the modulator, and has a poweramplifier as well as an output for providing a signal to be transmitted;and an antenna, which is coupled at one input to the output of thetransmission amplifier and is configured to transmit the signal to betransmitted; wherein the voltage supply arrangement is connected at thevoltage output to the transmission amplifier to supply voltage thereto.2. The transmission arrangement of claim 1, wherein the voltageconverter provides first and second voltage converter output voltages atone or more voltage outputs of the voltage supply arrangement, andwherein the voltage supply arrangement is connected to the modulator atthe second voltage output and at the one or more voltage outputs of thevoltage supply arrangement.
 3. The transmission arrangement of claim 1,wherein the modulator is configured to process the payload signal to betransmitted, and the transmission amplifier is configured to amplify themodulated signal using a polar transmitter principle.
 4. Thetransmission arrangement of claim 1, wherein the transmissionarrangement is coupled to the control input of the first switch or tothe control input of the second switch or both, such that the first orthe second switch or both modulate the amplitude of the signal beingtransmitted, in response to the payload signal.
 5. The transmissionarrangement of claim 1, wherein the power amplifier comprises a bipolartransistor, which is an amplifying component in the power amplifier, anda controllable resistance, which is coupled to a base of the bipolartransistor and, by means of a resistance control line, is coupled to thedrive circuit, and is configured to set a base current for the bipolartransistor such that an operating point of the bipolar transistor andthus a power provided from the power amplifier can be set in this way.